Harrison started donating in 1954 and after the first few donations it was discovered that his blood contained unusually strong and persistent antibodies against the D Rh group antigen. The discovery of these antibodies led to the development of immune globulin based products to prevent hemolytic disease of the newborn (HDN). These products, which contain a high level of anti-D antibodies are given to Rh(D) negative mothers of unknown or Rh(D) positive babies during and after pregnancy to prevent the creation of antibodies to the blood of a Rh(D) positive child. This antigen sensitization and subsequent incompatibility phenomenon causes Rhesus disease, the most common form of HDN.
Through the donations of his plasma, Harrison has helped prevent thousands of children from dying of HDN. This uniqueness was considered so important, that his life was insured for one million dollars after this discovery and the following research based on his donations created the commercial Anti-D immune globulin commonly known as RhoGAM. His blood plasma derivatives have since been given as treatment to one in ten pregnant women whose blood could potentially become incompatible with that of their children.
His donations were estimated to have helped save over 2.4 million babies, with pregnant women, including his own daughter Tracey, being treated with his antibodies.
There are only 43 people known to have been RHnull, but the actual number is expected to be much higher.
“Rhnull phenotype is a rare blood group with a frequency of approximately 1 in 6 million individuals, transmitted via an autosomal recessive mode. It is characterized by the weak (Rhmod) or lack (Rhnull) of expression of all Rh antigens on the red cells. The clinical significance of its assessment is that such patients with Rhnull syndrome are associated with chronic hemolytic anemia of varying degrees. Another clinical importance is that such subjects readily form alloantibodies when exposed to Rh antigens.We report herein a rare Rhnull phenotype in a sibling, which was detected as a part of the difficult sample work-up for red cell antibody screening and identification.”
Considering our current world population of 7,714,576,923 people (2019 estimate), 1 in 6 Million individuals being RHnull would come to
around 1,286 people worldwide being RHnull.
We expect the 1 in 6 Million number to be a decent estimate, but consider more accurate data being needed also reflecting local antigen frequencies and likelihood of 2 people meeting in those regions able to and actually producing offspring turning out to be RHnull.
